A conventionally known medical laser treatment device for relieving chronic pain in muscles, joints, etc., is, for example, a device that uses a semiconductor laser emitting near-infrared rays with a wavelength of 780 to 830 nm and having a laser beam output of 10 to 60 mW (Patent Document 1). The device comprises photosensors for detecting reflected light of a laser beam applied to the skin surface of the affected area. The photosensors are configured to detect the reflected light of the laser beam only when the laser beam irradiation port of the probe is in contact with the skin surface. When at least one of the photosensors does not detect laser reflected light, the laser beam irradiation is stopped.
Another known device is a near-infrared LED treatment device that can relieve various diseases, such as periarthritis humeroscapularis (frozen shoulder), muscular pain, gout, stiff shoulder, lumbago, rheumatoid arthritis, gonarthrosis, bruise, sprain, postherpetic neuralgia, pain in wound area, stress, and various other pains and swellings, by applying and permeating near-infrared rays from a light source that is a near-infrared light-emitting diode with a wavelength having excellent permeability into body tissue. The device can promote blood circulation and increase resistance, and has high safety (Patent Document 2).
[Patent Document 1] JP 1993-057026 A
[Patent Document 2] JP 2009-207605 A